The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 29, 2015
Filed:
Apr. 04, 2013
Satoshi Kikuchi, Shizuoka, JP;
Takanori Namba, Shizuoka, JP;
Masayasu Ito, Shizuoka, JP;
KOITO MANUFACTURING CO., LTD., Tokyo, JP;
Abstract
A semiconductor light source lighting circuit is provided with: a switching regulator that generates a drive current of a semiconductor light source using a switching element; and a control circuit that controls ON/OFF of the switching element. The control circuit is provided with: a comparator that compares the drive current and a target value; a counter that counts a digital value in a count direction determined by a comparison result of the comparator; a digital-analog converter that converts the digital value into an analog signal; and a drive circuit that controls the ON/OFF of the switching element based on the analog signal. The counter counts the digital value at a speed determined by an ON/OFF cycle of the switching element.